Arc-type melting furnaces have been proposed in the past for the melting of glass batch, slag, minerals, and other pulverant raw materials.
Typically, the arc is generated beneath a raw material layer or "blanket" which encompasses the lower ends of vertical electrodes and which forms an insulating top layer over the molten material in the furnace. Melting primarily takes place at the location of the spaced electrodes beneath the raw material blanket, and those raw materials which are located at the arcing locations melt more quickly and preferentially with respect to other portions of the batch blanket.
Arc stability and melting efficiency requires that a body of unmelted batch be constantly present at each of the arcing locations. Thus, the prior art formation of batch material or batch blanket of substantially equal depth across the top of the molten materials has resulted in the melting of that limited amount of material at each arcing location, and the batch material from other portions of the blanket is either inefficiently melted or must flow to the arcing location before it can be melted.
I have developed more efficient means and methods for batch material distribution to promote arc stability and melting efficiency. I have found that, in addition to a uniform blanket to batch material, a uniform level of molten material in the furnace also may be achieved. Because of the choke feed, melter power is controlled in direct response to any change in glass level.